( function () {
/**
 * peppers ghost effect based on http://www.instructables.com/id/Reflective-Prism/?ALLSTEPS
 */

class PeppersGhostEffect {
  constructor(renderer) {
    const scope = this;
    scope.cameraDistance = 15;
    scope.reflectFromAbove = false; // Internals

    let _halfWidth, _width, _height;

    const _cameraF = new THREE.PerspectiveCamera(); //front


    const _cameraB = new THREE.PerspectiveCamera(); //back


    const _cameraL = new THREE.PerspectiveCamera(); //left


    const _cameraR = new THREE.PerspectiveCamera(); //right


    const _position = new THREE.Vector3();

    const _quaternion = new THREE.Quaternion();

    const _scale = new THREE.Vector3(); // Initialization


    renderer.autoClear = false;

    this.setSize = function (width, height) {
      _halfWidth = width / 2;

      if (width < height) {
        _width = width / 3;
        _height = width / 3;
      } else {
        _width = height / 3;
        _height = height / 3;
      }

      renderer.setSize(width, height);
    };

    this.render = function (scene, camera) {
      scene.updateMatrixWorld();
      if (camera.parent === null) camera.updateMatrixWorld();
      camera.matrixWorld.decompose(_position, _quaternion, _scale); // front

      _cameraF.position.copy(_position);

      _cameraF.quaternion.copy(_quaternion);

      _cameraF.translateZ(scope.cameraDistance);

      _cameraF.lookAt(scene.position); // back


      _cameraB.position.copy(_position);

      _cameraB.quaternion.copy(_quaternion);

      _cameraB.translateZ(-scope.cameraDistance);

      _cameraB.lookAt(scene.position);

      _cameraB.rotation.z += 180 * (Math.PI / 180); // left

      _cameraL.position.copy(_position);

      _cameraL.quaternion.copy(_quaternion);

      _cameraL.translateX(-scope.cameraDistance);

      _cameraL.lookAt(scene.position);

      _cameraL.rotation.x += 90 * (Math.PI / 180); // right

      _cameraR.position.copy(_position);

      _cameraR.quaternion.copy(_quaternion);

      _cameraR.translateX(scope.cameraDistance);

      _cameraR.lookAt(scene.position);

      _cameraR.rotation.x += 90 * (Math.PI / 180);
      renderer.clear();
      renderer.setScissorTest(true);
      renderer.setScissor(_halfWidth - _width / 2, _height * 2, _width, _height);
      renderer.setViewport(_halfWidth - _width / 2, _height * 2, _width, _height);

      if (scope.reflectFromAbove) {
        renderer.render(scene, _cameraB);
      } else {
        renderer.render(scene, _cameraF);
      }

      renderer.setScissor(_halfWidth - _width / 2, 0, _width, _height);
      renderer.setViewport(_halfWidth - _width / 2, 0, _width, _height);

      if (scope.reflectFromAbove) {
        renderer.render(scene, _cameraF);
      } else {
        renderer.render(scene, _cameraB);
      }

      renderer.setScissor(_halfWidth - _width / 2 - _width, _height, _width, _height);
      renderer.setViewport(_halfWidth - _width / 2 - _width, _height, _width, _height);

      if (scope.reflectFromAbove) {
        renderer.render(scene, _cameraR);
      } else {
        renderer.render(scene, _cameraL);
      }

      renderer.setScissor(_halfWidth + _width / 2, _height, _width, _height);
      renderer.setViewport(_halfWidth + _width / 2, _height, _width, _height);

      if (scope.reflectFromAbove) {
        renderer.render(scene, _cameraL);
      } else {
        renderer.render(scene, _cameraR);
      }

      renderer.setScissorTest(false);
    };
  }

}

THREE.PeppersGhostEffect = PeppersGhostEffect;
} )();
